Mechanism for producing gyratory motion



Nov. 3, 1953 w. c. CONKLING 2,657,582

MECHANISM FOR PRODUCING GYRATORY MOTION Filed Sept. 27. 1950 2Sheets-Shet 1 INVEN TOR.

ATTU/m/[Xi Nov. 3, 1953 w. c. CONKLING 2,657,582

MECHANISM FOR PRODUCING GYRATORY MOTION Filed Sept. 27, 1950 2Sheets-Sheet 2 INVENTOR.

ATTORNEYS.

Patented Nov. 3, 1953 UNITED' STATES PATENT OFFICE MECHANISM FORPRODUCING GYRATORY MOTIO William 0. Conkling, Lockport, N. Y., assignorto Richmond Manufacturing Company, Lockport, N. Y., a corporation of NewYork Application September 27, 1950, Serial No. 186,958

9 Claims.

to provide an extremely simple and low cost eccentric weight type ofmechanism for producing gyratory motion which on starting produces smallcircles of gyration which increase in size until running speed isreached when circles of the desired amplitude are produced and which onstopping progressively decreases the amplitude of the circles until themechanism comes to rest. 7

Another object is to achieve such action on starting and stopping as afunction of gravity thereby to avoid sliding parts and return springswhich are subject to fouling with flour dust.

Another object is to provide such a mechanism which is convenientlyadjustable to produce circles of different sizes at running speed.

-Another object is to provide such a mechanism which is fully cushioned,particularly on starting and stopping, and is free from destructiveescaping vibrations while running, starting or stopping.

Another object is to provide such a mechanism which is adaptable tolarge sifters carrying heavy loads and to the space requirements imposedon such sifters.

Another object is to provide such a mechanism which can be driven from amotor on the sifter, from a belt running to the sifter or from a directdrive shaft above or below the sifter.

Another object is to provide such a mechanism which is simple andinexpensive in construction, reliable in operation, and which will standup under conditions of severe and constant use without getting out oforder or requiring repairs.

'Another object is to provide such a mechanism which is free fromfriction.

Other objects and advantages of the invention will be apparent from thefollowing description and drawings in which Fig. 1 is a side elevationalview of a mechanism embodying the present invention forv gyrating asifter, a part of the frame of which is illustrated. The mechanism isshown in its static state.

Fig. 2 is a horizontal section taken generally on line 2-4, Fig. 3.

One of the principal objects of the invention is Fig. 3 is a verticallongitudinal section taken generally on line 3-3, Fig. 2.

The mechanism embodying the present invention for producing gyratorymotion in a horizontal plane is shown as comprising a vertical shaft l0suitably journalled at its upper and lower ends in bearings II and I2one or both of which can be thrust bearings to support the shaft. Theupper bearing II is shown as being part of an upper spider I3 and thelower bearing I2 is shown as being part of a lower spider l4. Thesespiders can form part of the central frame structure of a high speedgyratory sifter, but since this frame structure forms no part of thepresent invention it is not illustrated in further detail.

The vertical shaft I!) can be rotated in any suitable manner and forthis purpose can be provided at its top or bottom with a projecting endI 5. This projecting end can be driven by an electric motor (not shown)mounted on the spider l3; a belt and pulley drive (not shown); or avertical drive shaft (not shown) having a universal and directlyconnected with the shaft end 5.

Between the bearings H and I2 the vertical shaft ID carries a pair ofspaced rectangular blocks 18 the vertical faces of which are parallelwith the axis of the shaft l0 and these blocks being preferably securedto the shaft I 0 by set screw l9. Each block [8 also has a pair of pins20 projecting horizontally from opposite sides thereof, the four pins 20being parallel and in vertical alinement with each other. A roller 2| isjournalled on each of these pins, preferably by roller bearings toreduce friction, and each roller is preferably radially flanged, asindicated at 22, on one side.

The blocks l8 are flanked by vertical plates 23 each having a verticalflange 24 along the vertical edge nearest the shaft It! when themechanism is at rest as shown in the drawings. These vertical flanges 24project outwardly or away from each other and are secured together by avertical gang of weights 25. The purpose of the flanges 22 of therollers 2| is to restrain the plate and weight assembly from cocking andto space the plates 23 from the blocks 18. These weights are preferablymade of roughly cast non of C-shaped form in horizontal section eachbeing idented, indicated at 26, so that the corresponding weights fitaround the blocks [8, and each weight being secured to the flanges 24 byscrews 28. As shown, these weights 25 are in a vertical gang, a columnof four weights being shown. It will therefore be seen that this gan ofweights 25 is, in effect, a vertically elongated weight.

Each plate 23 is provided with upper and lower arcuate slots 29 whichare arranged to receive the rollers 2| and which curve downwardly awayfrom thever'tical shaft [8. Tr1 e'-tipter-5ewerk ing edge of each of theupper slots" has welded thereto an arcuate hardened rail 30. Each of thelower slots 29 also has welded thereto arr arcuate hardened rail 3|. Thereason for the arrangement of the hardened rails" 33 along the} topedges of the upper arcuate slots 29 and of the hardened rails 3|alongtlie: lower eageeesthe lower arcuate slots 29 is tllettthe gang offweights tend to tip in a corresponding direction and hence establishthese rails as the working surfaces.

Each plate 23 is also provided with an upper and a lower series of holes32 extending toward the shaft l, eachhole of the upper series beingpreferably in vertical alinement with-a cone-- spending hole of thelo'vi'rer' series and the holes of the two plates 23 alininghorizontally with one another. The series of holes 3Z1are preferably;

but not necessarily-arranged at an angle incli'ne'd to conform tothearcu'ate' slots 29.

A: removable" pin 33 extends through a corresponding: pair of the upperseries of holes 32 in thetwo plates 23 andcanj be moved to extendthrough any pairof these holes thereby to adjl'istthe position or thispin with reference td the gang ofweights For this purpose the pin 33"isprefera-bly in the form of a bolt having a head 34 at one end and anut35 at it's'oppo'site end so that it can readily be pulled out from onepair ofthe-two upper'series of holes 32- and replaced in another" orthese pairs of holes;

This pin 33 carries; bet-ween the plates 23,- a square block 36 to oneface of which the upper end or a leaf spring 38 is secured; This leafspring; hangs from this block and preferably arches toward the verticalshaft f'll. At its lower end this spring bears against aroller' 396151 apin 40 extending through a correspondinghole 32 of the-"lower series of'th'e'se holes; pin

la-is also replaceable in any pair of holes 3 2 of" the lower series inthe two plates 23 andhence is preferably'ir'r the formof abolt having ahead 4| atone end and: a nut at its oppositeend so that it can bereadily pulled out from one pair erthe two lower series of holes 32 andreplace another or these pair wholes:

Secured, asby bolts 43, to the center of the leaf spring '38 is a;second vertically'arrangd arched leafv spring 44- which;- However; bowsoppositely to the'leaf spring 33 so that its ends project to ward thegang of weights 2 5. This l'astarched leaf spring 44" is preferablyfaced Wltllleather 45 and its ends are arranged toengage the meme Themechanism is particularly designed rotehigh speed gyrat'dry sifter t6 bedriven at from;-

say; 180' to 300' revolutions per minute with from say,- 2 to 4 inchcircles; With the sifterhavingj say, a natural frequency or30revclut-ions or pendulum' like gyrations per minute; determined by theeffectivelhgth- 0f the flexible suspension-,

until the sifter gets te gyrate' abeve this naturalfrequencyp'erfectcircle's are impossible since natural-frequency may becarrying-the sifter' frame in one direction and the weights 25 samedirection with ado'iible'd unbalancing' force; 1

Accordingly before ar a after the s'i-fter is run: ning at full speed itis desirable that it describe trircgarreree acting on the weights 25causes 4 smaller circles since otherwise there would be excessiveescaping vibrations due to the fact that the circles are not perfect,

To accomplish this the center of gravity of the gang of weights 25 isinitially arranged near the axis of the vertical shaft Ill whichpreferably iaterseets center of gravity: of the' Sifter. It w-i-lr-teunder-steed; however, tfiatthe center of gravity of the gang of weightsmust initially be slightly on the side of the axis of the shaft llremote-from the leaf springs 33 and 44. Accordingly as this "shaftstarts to rotate the weights have relatively small efiect in gyratingthe erdescribes relatively small cir- Asthhalf't' Hl picks up in speedthe centhem' to move' radially outwardly, the rollers 2| riding down thehardened rails 30 and 3| and hence-the weights also rising vertically,In this action the gang of weights 25 have a tendency totip andhence-the hardened rail 30 is disposed along the topof its slot 29 whilethe hardened rail" 3| is disposed along the bottomof its slot 2-9;

As the shaft M" reaches its maximum speed the rollers 21' approach closeto the bottoms of the 'arcuate' slots 29 and'the ends of the leatherfaced leaf spring" mt. engage the blocks |8. This causes this spring andlts supporting leaf spring 38*to' flatten 0111; against the pins 33 and40', these springs thereby serving as a resilient stop to the outwardmove ment of the gang of weights 25. The springs 38 act as positivestops which prevent complete bot:

toming of the rollers 21 in the bottoms of the slots 29'. The resiliencyprovided by these leaf springsprevents jarring or the sifter as it isbrought" under control to describe running circles of the desiredamplitude;

The size of these running circles ofgyration can easily be'adju'ste'cl.'ThlllS th' Sifter is $817" to gyrate with circleso'f maximum"amplitude. If smaller circles are desired, the bolts 33 and 40 areremoved and replaced in the next higher closer to these weights andhence" these weights are stopped closer to the axis of'the" shaft tothis shaft reaches full running speed circles; at running speed, ofsmaller amplitude result;

It will particularly be noted that these bolts 33 and 40 are readilyreplaced to secure the dc sired circular orbit of the sifter. There isno need to jack up the-weights 25 or to undertake anycther difficultwork.

When the driving force is relieved from the vertical shaft l0 itgradually slows down and" sincedecr-easing centrifu al force isapp'li'edto the weights 25 they gradually lower by gravity the' rollers-21 riding up the arcuate" slots 2-9 and the gang of weights-comingcloser to the axis of? the'shaf-t m as the sitter comes to rest; Accord:ingly as the rate of gyration of the Sifter falls below the naturalfrequency thereof the size of. the circles generated. is" sfnall andthe" unbalance of the forces do not set up a pronounced walkingv orcradling action of thesifte'r;

In the action of the sifter, the shape of the arcrxateslots 29 isimportant. Thus, it will be noted that" the slope of the rails of eachof" these' slots increases tdwa'rd its lower end.

cordingly as a result of the action of the inclined rails on the rollersthere is a restraining horizontal force to the movement of the gang ofweights 25 which increases-with the movement of the weights from: theaxis of the shaft If). This is desirable as the centrifugal force of thegang of weights is proportional to the length of the radius from thecenter of the shaft 18 to the center of gravity of the weights 25.Accordingly it is desirable that the horizontal component due to theaction of the rollers in the slots 29 increases at a greater rate thanthis radius so that there is no tendency for a sudden outwardmovement ofthe weights due to the increase in centrifugal force as they moveoutwardly. Expressed in another way, the form of the rails of thearcuate slots 29 is such that the horizontal force opposing movement ofthe weight 25 away from the shaft I9 increases at a greater rate thanthe centrifugal force of the weight increases.

From the foregoing it will be seen that the present invention providesan extremely simple and low cost mechanism for gyrating heavy siftersand the like which is easily adjustable to produce different amplitudesof gyration at running speed, is free from tendency to foul, andaccomplishes the many objects enumerated.

I claim:

1. A mechanism for producing gyratory motion, comprising a verticalshaft, a pair of vertical plates flanking said shaft, a verticallyelongated weight connecting said plates and arranged adjacent said shaftin the static condition of the mechanism, means for guiding said platesto cause an upward movement of said weight away from said shaft, and astop interposed between said plates on the side of said shaft oppositefrom said weight and arranged to limit the horizontal movement of saidweight away from said shaft.

2. A mechanism for producing gyratory motion, comprising a verticalshaft, a pair of vertical plates flanking said shaft, a verticallyelongated weight connecting said plates and arranged adjacent said shaftin the static condition of the mechanism, means for guiding said platesto cause an upward movement of said weight away from said shaft, and astop resiliently mounted on said plates and interposed therebetween andcoacting with said shaft to limit the horizontal movement of said weightaway from said shaft.

3. A mechanism for producing gyratory motion, comprising a verticalshaft, a pair of vertical plates flanking said shaft, a verticallyelongated weight connecting said plates and arranged adjacent said shaftin the static condition of the mechanism, means for guiding said platesto cause an upward movement of said weight away from said shaft, a stopinterposed between said plates on the side of said shaft opposite fromsaid weight and arranged to limit the horizontal movement of said weightaway from said shaft, and means for shifting said stop horizontallyalong said plates toward and from said weight.

4. A mechanism for producing gyratory motion, comprising a verticalshaft, a pair of vertical plates flanking said shaft, a verticallyelongated weight connecting said plates and arranged adjacent said shaftin the static condition of the mechanism, means for guiding said platesto cause an upward movement of said weight away from said shaft, a stopresiliently mounted on said plates and interposed therebetween andcoacting with said shaft to limit the horizontal movement of said weightaway from said shaft, and means for shifting said stop horizontallyalong said plates toward and from said weight.

5. A mechanism for producing gyratory motion, comprising a verticalshaft, a pair of vertical plates flanking said shaft, a verticallyelongated weight connecting said plates and arranged adjacent said shaftin the static condition of the mechanism, means for guiding said platesto cause an upward movement of said weight away from said shaft, a crossbolt insertable through registering holes through said plates of aseries of holes extending horizontally toward said shaft from the sidethereof opposite said weight, and

a stop on said cross bolt between said plates and,

coacting with said shaft to limit the horizontal movement of said weightaway from said shaft.

6. A mechanism for producing gyratory motion, comprising a verticalshaft, a pair of vertical plates flanking said shaft, a verticallyelongated weight connecting said plates and arranged adjacent said shaftin the static condition of the mechanism, means for guiding said platesto cause an upward movement of said weight away from said shaft,comprising a pair of vertically spaced blocks fast to said shaft, a pairof coaxial rollers projecting in opposite directions from each of saidblocks with their axes arranged perpendicularly to said plates and eachroller riding in an inclined guideway provided in the adjacent part ofthe corresponding plate, said guideways being generally parallel withone another, a pair of resilient stops interposed between said plates onthe side of said shaft opposite from said weight and each arranged toengage a corresponding one of said blocks to limit the horizontalmovement of said weight away from said shaft, and means for shiftingeach of said stops horizontally along said plates toward and from saidweight.

7. A mechanism for producing gyratory motion, comprising a verticalshaft, a pair of vertical plates flanking said shaft, a verticallyelongated weight connecting said plates and arranged adjacent said shaftin the static condition of the mechanism, means for guiding said platesto cause an upward movement of said Weight away from said shaft,comprising a pair of vertically spaced blocks fast to said shaft, a pairof coaxial rollers projecting in opposite directions from each of saidblocks with their axes arranged perpendicularly to said plates and eachroller riding in an inclined guideway provided in the adjacent part ofthe corresponding plate, said guideways being generally parallel withone another, a leaf spring interposed between said plates on the side ofsaid shaft opposite from said weight and having its opposite endsarranged to engage said blocks to limit the horizontal movement of saidweight away from said shaft, and means for shifting said leaf springhorizontally along said plates toward and from said Weight.

8. A mechanism for producing gyratory motion, comprising a verticalshaft, a pair of vertical plates flanking said shaft, a verticallyelongated weight connecting said plates and arranged adjacent said shaftin the static condition of the mechanism, means for guiding said platesto cause an upward movement of said weight away from said shaft,comprising a pair of vertically spaced blocks fast to said shaft, a pairof coaxial rollers projecting in opposite directions from each of saidblocks with their axes arranged perpendicularly to said plates and eachroller riding in an inclined guideway provided in the adjacent 7 part ofthe correspondin plate, said guideways being generally parallel with oneanother, a vertical leaf spring interposed between said plates am theside: (if. mm; dppm'site; 1mm. said wefgm, a, 2mm seua ing' cm'eeimefsaid l'eaiflspfingi t6 5am platefi and ins-mama regi stexmg pairs.0 h0Ie= tmrcxugri smich 'lxes of. a1 sefisszextnmg hz izbntal'ly'towrdlsaixfl shsalft, whacking baht engagin me rather em of saiei leaf spring:max-table in lfgisfi'ringf pairs 0:? moles thrcm'gh: sa'i dplfies of aseries extending homronml ly rim midi'sa id shaftana'a: semndi-lisafisprin seamed at;- i deiiiiral pwrt; ad the Gamma part; at san dfirsi; spring, the: ends oi saiki s'eeond Ieaif sptii ig Being n-gzigeasbl; with said blo iks w limit jhe duffiweimi-moverhnfiof sai'dweignt relative to said Sm lavfifiany as a unitary structuretransversely of mvemept of s'aiid wigm away from saidlshaft 2,516,207

ix'imwszsessv at a" gzwterur ste; i centnifizgnk farce increases,comprising a. guide: slbl' and roller plates and saidshaflz,m-laasecandguide sIot on Sam. guide si ots, me Siam condifian of ummechanism, being" disposed on the side ofisadd shaft'hopiwsite fimm-saidone side-thereof;

WILLIAM C; CONKLING,.

R fimw sfii ed; h le 1' his nt WEED S TES PA' EN' Name Date Climbs Jun-ea; 1 915 Number its l'ower end arrangedremote; imm- Heberbrand- June 4,was: Hartwi'g July 25;, W

